They call it “the Starbucks sound.” It is meant to serve as a placid soundtrack to your Starbucks coffee-drinking experience. It is not, as you might expect, the sound of dual cash registers chiming in unison as five automatic milk foamers screech in disharmony as 12 kids from eight different minivans march in and scream their want of a dozen grande Tazo strawberry high-fructose chai tealike milkshake things as their wary parents whip out the credit card and sigh and yell at the kids to please shut the hell up.